Bag



Jan. 30, 1.9 62 A, F, KEATING 3,018,943

BAG

Filed July 27, 1959 FIGS.

2 Sheets-Sheet 2 United States lemis Bro. Bag Company, St. Louis, Mo., acorporation of Missouri Filed July 27, 1959, Ser. No. 829,571 8 Claims.(Cl. 229-625) This invention relates to bags, and more particularly tovalve bags made of plastic-lined cloth.

The invention is particularly concerned with sewn valve bags made ofplastic-lined cloth, such as a bag made of material having an outerlayer of burlap and an mner layer of polyethylene and having a valveprovided with a paper valve sleeve at one corner of the bag. Inparticular, the invention has been applied to a bag made of materialconsisting of an outer layer of burlap, an intermediate layer of crepedkraft paper and an lnner layer of sheet polyethylene, with asphaltbetween the layers. In the manufacture of such bags, the sleeve isinserted by hand in the end of the bag at the valve corner prior toclosing the end of the bag and provision must be made for holding it inplace during subsequent operations. The hand operation does not lenditself to adhesive securement of the sleeve directly to the polyethylenelining, and it.has heretofore been the practice to staple the sleeve tothe bag body to hold 1t in position, the staples being removed afterthey have served their-purpose. 'Ibis procedure is time-consuming.

Accordingly, among the several objects of the invention may -be notedthe provision of a new construction for bags of the class abovedescribed which enables the sleeve to be adhered in position at thevalve corner, in such `manner as to hold it in proper position duringthe rformation of the valve and the sewing of the end of the bag, andalso to provide a complete adhesive seam between the valve ap and an endof the sleeve overlapping the valve ap.

Another object `of the invention is the provision of a construction suchas described wherein the sleeve is a sleeve of the so-called tuck-intype, having a reversely folded portion extending out of the bag throughthe valve opening, this portion being adapted after the bag has beenfilled by means of a lling spout extending through the sleeve and intothe bag, to be folded up and tuckedinrgto Iclose the sleeve. A furtherobject of the invention is the provision of a construction such asdescribed which facilitates the sewing of the end of the bag, especiallyin the area of the valve.

Otherf objects and features will be in par-t apparent and in partpointed out hereinafter.

The invention accordingly comprises the constructions hereinafterdescribed, the scope of the invention being indicated in the followingclaims.

In the accompanying drawings, in which one of various possibleembodiments of the invention is illustrated:

FIG. l is a plan view of a composite multiply web from which bags ofthis invention are made, certain plies and laminants of the web beingshown broken away in part;

FIG. 2 is an enlarged section taken on line 2 2 of FIG. l, thicknessesbeing exaggerated; t Y

FIG. 3 is a view in elevation of a bag bvody made from a blank segmentedfrom the FIG; 1 web in an intermediate condition thereof;

FIG. 4 is a view in elevation of the bag body turned inside out from itsFIG. 3 condition -to bring it into its t final condition, and showing avalve sleeve inserted at the valve corner;

FIG. 5 is a plan view of the valve sleeve per se;

3,918,943 Patented Jan. 30, 1962 FIG. 6 is a perspective view showinghow the sleeve is inserted in the bag body;

FIGS. 7 and 8 are views illustrating steps in the forma tion of thevalve;

FIG. 9 is a View in elevation of a completed bag; and,

FIG. l0 is a longitudinal vertical section through the valve. p

Corresponding reference characters indicate corresponding partsthroughout the several views of the drawings.

FIGS. 1 and 2, of the `drawings show a Iweb 1 of composite bag materialfrom which are segmented rectangular blanks to be formed into bags ofthis invention. This web is essentially a three-ply web, comprising alayer or ply 3 of cloth, more particularly burlap, a layer or ply 4 ofpaper, more particularly creped kraft paper, and a layer or ply S ofexible sheet plastic material, more particularly polyethylene. The pliesare laminated by means of laminant 7, more particularly asphalt. It willbe understood that web 1 may be formed by applying molten asphaltbetween the plies and combining the plies, the asphalt on cooling actingto hold the plies together. The paper 4 and asphalt 7 terminate short ofone of the longitudinal edges of the web, leaving unadhered marginalportions 3a and 5a of the burlap and polyethylene plies along this edgeof the lweb (its upper edge as viewed in FIGS. 1 and 2). Also, in thecourse of the formation of the web, a relatively narrow paper strip 9 iscombined with the web extending along the stated one longitudinal edgethereof on the polyethylene ply S, this strip being secured to thepolyethylene ply by a layer 11 of asphalt therebetween. The outer edgeof the strip 9 is generally coincident with fthe edges of the plies 3and 5. Asphalt 11 extends throughout the width of strip 9. The paper ofwhich strip 9 is composed is preferably of such nature that there is nosubstantial bleeding of asphalt therethrough.

Web 1 is cut on lines such as indicated at 13 in FIG. l to segment itinto rectangular bag blanks 15 each having a width correspondingV totwice the desired bag width and Y a height (the width of web 1)corresponding to the desired bag height. Each such blank is folded inhalf on a heightwise fold line 17 with the burlap 3 on the inside andthe polyethylene 5 and paper strip 9 on the outside, and a seam 19 issewn along the edge (the lower edge) of the folded blank opposite theedge where the paper strip is situated and aseam 21 is sewn along theedge opposite the fold line 17 (see FIG. 3). Seam 19 constitutes abottom seam; seam 21 constitutes a side seam. Fold 17 constitutes theother side of the bag from side seam 21. In the sewing of these seams,the needle of the sewing machine tends to become heated due to friction,thereby tending to melt the asphalt at the holes made by the needle, themelted asphalt tending to run into and plugging the holes. Then the sewnblank of FIG. 3 is turned inside out to provide a bag body B such asshown in FIG. 4 in which the burlap 3 is on the outside, and thepolyethylene 5 and paper strip 9 on the inside, the latter being locatedat the open upper end of the bag body. The polyethylene 5 thenconstitutes a liner.

FIG. 5 illustrates a valve sleeve 23 per se, in its initial state, priorto application to the bag body B. As shown, this sleeve comprises agenerally'rectangular blank of paper, such as creped kraft paper. It hasa plastic coating 25, such as a polyethylene coating, on one facethereof (which is its face away from the viewer as illustrated in FIG.5). This blank is folded in half on a longitudinal center line 27, withits polyethyene-coated face on the inside, and has a stripe 29 ofadhesive (any suitable paste vor glue) applied to its plain uncoatedface (which is then on the outside of the folded blank) at one end. Thesleeve 23, so folded, is then inserted with its adhesive-carrying endfirst i-n the corner at the open end of the bag body at the upper end ofside fold 17 to dispose the stripe of adhesive 29 against the paperstrip 9 and to cause the sleeve Vto become adhered to the paper strip 9(see FIGS. 5 and 6). v

The `sleeve 23, together with a triangular portion 31 of the bag bodywhich forms a valve ap, is folded into the open end ofthe bag asillustrated in FIG. 7. A portion 23a of the sleeve is folded back on atransverse fold line 33 lying inward from the inner end edge 35 of thevalve ilap 31 to extend back outward over the valve ap (see FIG. 8).This leaves a relatively short portion 23h of the sleeve extendinginward from the inner end edge 35 of the valve ap, this portion 23bbeing adhered to the inside of the inner margin of the valve ap byreason of adhesive 29 securing it to the paper strip 9. As the valveformation is completed, the portion 23b of the sleeve becomes reverslyfolded on center line 27 as regards the initial folded condition so thatthe coated face of portion 23b is on the outside of the reverse-foldedportion 23b. Portion 23a becomes folded on center line 27 in such mannerthat the coated face thereof is on the inside. Corners 37 of the sleevefold over between the sides of the valve flap 31 and the bag walls.These are of no consequence, and could be eliminated, if desired, bytrimming off the corners of the sleeve when it is originally made.

Finally, the open end of the bag is closed by running 'a line ofstitching 39 across the top of the bag through the unadhered marginalportions 3a and 5a of the burlap and polyethylene plies 3 and 5. Thisline of stitching constitutes the top seam of the bag. It extendsthrough and Secures together the upper margins of the folded sides ofthe sleeve so that the sleeve is formed into a tube adapted to receive afilling spout. The stitching is run olf the side of the bag andthroughout the length of the outwardly extending tuck-in portion 23a ofthe sleeve. jIn sewing the line of stitching 39, the needle of thesewing machine tends to become heated `due to friction, tending to meltthe asphalt 11 between the paper strip 9 and the polyethylene 5, themelted asphalt tending to run into and plugging the needle holes.Omission of paper layer 4 and asphalt between the margins 3a and 5a ofthe burlap and polyethylene makes it easier to sew the top seam 39,particularly at the right-hand end of the upper margin of the bag wherethere is of necessity a considerable thickness of paper, 'polyethyleneand burlap.

Thus, the bag B 'as completed (see FIGS. 9 'and 10) has 'a valve at theright-hand corner at its upper end,

the valve being constituted by the intucked valve flap 31 at this cornerand by the paper sleeve Y23 extending from the valve flap. The sleeveincludes the reversely folded tuck-in portion 23a extending out of thebag adapted after the baghas been filled by means of a lilling spoutextending through the sleeve and into the bag to be folded up and tuckedin to close the sleeve. The inside of this tuckin portion 23a bears thepolyethylene coating 25. 'Ihe Sleeve is adhesively secured to valve ap31 throughout `the width of the sleeve. This adhesive securement ispresent during the manufacture of the bag to hold the sleeve 'in properposition during the formation of the valve and the sewing of the end ofthe bag.

In view of the above, it will be seen that the several Objects of theinvention are achieved and other advantageous results attained.

As various changes could be made in the above constructions withoutdeparting from the scope of the inventi'on, Vit `is intended that allmatter contained in the above `description or shown in the accompanyingdrawings 'shall be Vinterpreted as illustrative and not in a limitingsense.

I claim:

l. A bag comprising a rectangular blank of material -consisting of anouter layer of burlap, an intermediate layer of paper and an outer'layer of flexible sheet polyethylene laminated by means of asphalt,said blank being folded in half on a fold line which constitutes oneside of the bag with the polyethylene layer on the inside and havingsewn seams at the bottom, the top and the other side, said blank havinga strip of paper laminated to the polyethylene by means of asphaltextending completely around the upper margin of the bag on the insidethereof, said bag having a valve constituted by an intucked valve ap atthe corner thereof situated at the upper end of the folded side of thebag and a paper sleeve extending from the valve flap, said valve flaphaving a central fold spaced from the upper end of the bag, said sleevebeing folded in half on a generally central fold in line with thecentral fold of the valve ap, an end poition of the sleeve lapping saidpaper strip and being secured thereto by adhesive, the upper margins ofthe sleeve being stitched together by the bag top seam.

2. A bag as set forth in claim l wherein the adhesive which secures thesleeve to the valve flap is on one face of the sleeve and the other faceof the sleeve is coated over its entire area with polyethylene.

3. A bag as set forth in claim 1 wherein the sleeve is folded back on atransverse fold line located inward of the inner end edge of the valveap to have a tuck-in portion extending out through the valve ap, theupper margins of said tuck-in portion being stitched together by acontinuation of the bag top seam.

4. A bag as set forth in claim 3 wherein the adhesive which secures thesleeve to the paper strip is on one face of the sleeve and the otherface of the sleeve is coated over its entire area with polyethylene sothat the inside of the tuck-in portion of the sleeve ispolyethylenecoated.

5. A bag as set forth in claim l wherein the paper layer and the asphaltlaminant terminates short of the upper edges of the burlap andpolyethylene layers, leaving unlaminated upper marginal portions of theburlap and polyethylene layers, the stitching for the bag top seamextending through said unlaminated upper marginal portions.

6. A bag as set forth in claim 5 wherein the upper edge of the paperstrip is generally coincident with the upper edges of the burlap andpolyethylene layers and the asphalt laminant for the paper strip andpolyethylene layer extends throughout the width of the paper strip.

7. A bag comprising a rectangular blank of material consisting of anouter layer of cloth, an intermediate layer of paper and an outer layerof flexible sheet plastic laminated by means of a laminant, said blankbeing folded in half on a fold line which constitutes one side of thebag with the plastic layer on the inside and having sewn seams at thebottom, the top and the other side, said blank having a strip of paperlaminated to the plastic by means of a laminant extending completelyaround the upper margin of the bag on the inside thereof, said baghaving a valve constituted by an intucked valve ap at the corner thereofsituated at the upper end of the folded side of the bag and a papersleeve extending from the valve flap, said valve flap having a centralfold spaced from the upper end of the bag, said sleeve being folded inhalf on a generally central fold in line with the centrol fold of thevalve flap, an end portion of the sleeve lapping said paper strip andbeing secured thereto by adhesive, the upper margins of the sleeve beingstitched together by the bag top seam.

8. A bag comprising a rectangular blank of multi-ply material includingan outer ply of flexible sheet plastic laminated by means of a laminantto the next adjacent ply, said blank being folded in half on a fold linewhich constitutes one side of the bag with the plastic ply on the insideand having sewn seams at the bottom, the top and the other side, saidblank having a strip of paper laminated to the plastic by means of alaminant extending completely around the upper margin of the bag on theinside thereof, said bag having a valve constituted 6 by an intuckedvalve flap at the corner thereof situated References Cited in the fileof this patent at the upper end of the folded `side of the bag and aUNTTED STATES PATENTS paper sleeve extending from the valve flap, saidvalve flap having a central fold spaced from the upper end 21511068Weeks Aug' l 1950 of the bag, said sleeve being folded in half on a gen-5 2595446 Brady c May 6 1952 orally central fold in line with thecentral fold of the 2635803 Hartman Apr' 21 1953 valve flap, `an endportion of the sleeve lapping said paper FOREGN PATENTS strip and beingsecured thereto by adhesive, the upper 448,011 Canada APL 20, 1948margins of the sleeve being stitched together by the bag top seam. 1()

1. A BAG COMPRISING A RECTANGULAR BLANK OF MATERIAL CONSISTING OF ANOUTER LAYER OF BURLAP, AN INTERMEDIATE LAYER OF PAPER AND AN OUTER LAYEROF FLEXIBLE SHEET POLYETHYLENE LAMINATED BY MEANS OF ASPHALT, SAID BLANKBEING FOLDED IN HALF ON A FOLD LINE WHICH CONSTITUTES ONE SIDE OF THEBAG WITH THE POLYETHYLENE ON THE INSIDE AND HAVING SEWN SEAMS AT THEBOTTOM, THE TOP AND THE OTHER SIDE, SAID BLANK HAVING A STRIP OF PAPERLAMINATED TO THE POLYETHYLENE BY MEANS OF ASPHALT EXTENDING COMPLETELYAROUND THE UPPER MARGIN OF THE BAG ON THE INSIDE